Cisco Cisco Email Security Appliance X1050 Guía Del Usuario
13-10
Cisco AsyncOS 8.5 for Email User Guide
Chapter 13 Anti-Spam
Defining Anti-Spam Policies
You can change the positively identified spam threshold to a value between 50 and 99. You can change
the threshold for suspected spam to any value between 25 and the value you specified for
positively-identifed spam.
the threshold for suspected spam to any value between 25 and the value you specified for
positively-identifed spam.
When you change the thresholds:
•
Specifying a lower number (a more aggressive configuration) identifies more messages as spam and
may produce more false positives. This provides a lower risk that users will see spam but a higher
risk of having legitimate mail marked as spam.
may produce more false positives. This provides a lower risk that users will see spam but a higher
risk of having legitimate mail marked as spam.
•
Specifying a higher number (a more conservative configuration) identifies fewer messages as spam
and may deliver more spam. This provides a higher risk of users seeing spam but less risk less risk
that legitimate mail will be withheld as spam. Ideally, if set up correctly, the message subject will
identify the message as likely spam and message will be delivered.
and may deliver more spam. This provides a higher risk of users seeing spam but less risk less risk
that legitimate mail will be withheld as spam. Ideally, if set up correctly, the message subject will
identify the message as likely spam and message will be delivered.
You can define separate actions to take on positively-identified and suspected spam. For example, you
may want to drop “positively identified” spam but quarantine “suspected” spam.
may want to drop “positively identified” spam but quarantine “suspected” spam.
Related Topics
•
•
Configuration Examples: Actions for Positively Identified versus Suspected
Spam
Spam
The aggressive example tags only suspected spam messages, while dropping those messages that are
positively identified. Administrators and end-users can check the subject line of incoming message for
false positives, and an administrator can adjust, if necessary, the suspected spam threshold.
positively identified. Administrators and end-users can check the subject line of incoming message for
false positives, and an administrator can adjust, if necessary, the suspected spam threshold.
In the conservative example, positively identified and suspected spam is delivered with an altered
subject. Users can delete suspected and positively identified spam. This method is more conservative
than the first.
subject. Users can delete suspected and positively identified spam. This method is more conservative
than the first.
For a further discussion of aggressive and conservative policies in mail policies, see
in the Mail Policies chapter.
Spam
Sample Actions
(Aggressive)
(Aggressive)
Sample Actions
(Conservative)
(Conservative)
Positively
Identified
Identified
Drop
•
Deliver with “
[Positive Spam]
” added
to the subject of messages, or
•
Quarantine
Suspected
Deliver with “
[Suspected Spam]
”
added to the subject of messages
Deliver with “
[Suspected Spam]
” added to
the subject of messages